Studies on Substrates, Inhibitors and Modifiers on the High Affinity Choline Transport-Acetylation System Present in Rat Brain Synaptosomes

Abstract

Several laboratories have demonstrated a requirement for the high affinity transport of choline (Ch) in the synthesis of ACh by intact synaptosomes (3, 18, 19, 22, 27). Particularly striking are those results which show an almost total conversion of Ch transported by the high affinity carrier to ACh (27), and which suggest that the high affinity carrier is present only at cholinergic nerve terminals (22, 26). These observations led us (3–5) and others (23, 25) to propose and test the hypothesis that the high affinity transport and acetylation of Ch by nerve endings are coupled in some manner.